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4G LTE and LE

The hottest topic in law enforcement is the recently launched cell network, 4G LTE (Long Term Evolution). At least, it is the hottest topic among public safety information technology professionals, and it is coming to a police radio or cell phone near you. Recently highlighted at the IACP, APCO and IWCE conferences, 4G LTE is probably the biggest step toward realistic and widespread interoperability since 9/11. The speed of data-image file transfers is the biggest step toward true, wireless, real-time streaming.

The 700 MHz Band comprises 108 megahertz of spectrum from 698 to 806 MHz and is designated for commercial and public safety uses. This is indeed the sweet spot for emergency communications. The progress has been steady. First, 2G (GSM/Edge/CDMA), then 3G (EV-DO/WiMax) and now 4G LTE. And 4G-IMT-Advanced is coming soon.

“Fast” is hard to explain because it is relative. Remember when DSL was fast? The 4G LTE average data rates in real-world, loaded network environments are 5 to 12 megabits on the downlink and 2 to 5 Mbps on the uplink. OK, 4G LTE is expected to be 10 to 15 times faster than 3G, but what does that really mean?

At the Verizon Wireless booth during IACP, we watched an image file transfer from a patrol in-car video to a remote precinct. (LTE is the technology used by Verizon Wireless and AT&T.) While already running 5 megs of streaming video, the 8 meg transfer took just 10 seconds.

Also of significant interest are the upcoming interop possibilities thanks to a collaboration between Catalyst Communications and Verizon Wireless on 4G LTE. Using real gee-whiz technology, a land mobile radio (LMR), i.e., a police radio on 800 MHz, can talk to a Sprint/Nextel push-to-talk (PTT) cell phone on the 3G network and a Verizon Wireless PTT cell phone on its 4G network.

That’s right, a police radio was keyed up on one network, and the voice came over both a Sprint cell on another network and a Verizon cell on yet another network. All three could send; all three could receive. Complete interoperability.

That, in turn, casts emergency communications in a whole different light—that first responders would use cell phones in addition to, instead of, or right along with, the police radio. But what if the cell tower goes down or is overloaded with disaster volumes of traffic? After all, the biggest fear of public safety using cell networks in a crisis is that the cell tower or network will go down.

Many of us think “our” LMR systems are more reliable than “their” cell networks. That is probably not true. Even if it is, their towers or networks can be put back up a lot faster than ours. They call it “resilience,” and it means getting cell towers or switch centers back into operation, or adding cell capacity when needed in a particular crisis location. In fact, some locations that these crisis management teams have already responded to didn’t have good LMR coverage in the first place.

Verizon Wireless calls its portable cell sites COWs (Cells on Wheels) and COLTs (Cells on Light Trucks). These can be moved into locations where the cell is damaged, disabled or overloaded.

This technology may be beyond everyone but IT personnel. The facts is, however, that real solutions to real problems are on the way. Expect to see the first 4G LTE capability in modems and air cards. Then it will be embedded in smartphones. By 2013, 4G LTE will have the same coverage as 3G does today.